First you pay qadha of 2017 and as you mentioned that there some from last year those you may pay after the holy month of Ramadhan. Now issue of kaffara; you can send the money to your home town or the place where you can find poor people. These days it has become very easy. You may send in minutes by net banking or western union or other legal method of transferring money to overseas. If for some reason you were unable to send in the month of Ramadhan Ul Mubarak you don’t need to pay any extra amount.